Transformer.



W. M. DANN.

TRANSFORMER.

APPLICATION FILED AUG. 7, MIL

Patented Mar. 2, 1915;

/ ATTORNEY WALTER M. DANN, or wrrxmssnnc, rnnnsinvianm, ASSIGNOR To wnsrmerrousn ELECTBIG AND mmzrmcruame commen s; coaronarron or rnnnsvnvama.

rmirsro itmsn.

To all whom it may concern Be it known that I, WALTER M.'DANN, a citizen of the United States, and a resident 'ofWilkinsburg, in the county of. Allegheny ings such as usually accompanies a ground or short circuit on a powerful generating system.

Fi res 1 and 2 of the accompanying drawings are, respectively, an end and a side elevation, partially in cross section, of a transformer constructed in accordance with my invention.

Referring to the drawings, the transformer here shown comprises an annular laminated core member 1, having an insulating sheath 2, a secondary coil 3, the turns of which are uniformly distributed about the annular core member 1, an outer insulating sheath 4, a metal frame or casing 5, "and an insulating tube 6.

The casing 5 comprises two annular members 7 and 8 having base or foot projections 9 and 10, on which the transformer may be supported and "flanges 11 and 12, which substantially cover the outer surface of the insulating sheath 4. a The two parts are fastened together by bolts 13 and each of them is provided with a central opening 14, through which the tube 6 extends. The

tube is preferably held in position by insulating cement or some other suitable sealing compound. A conductor 15 extends through the tube 6 and constitutes the primary winding of, the transformer;

Speciflcation of Letters Patent.

Application filed August 7, 1911.

Patented Mar. 2, 1915. Serial No. 642,882. I

The annular punchings or laminae, of which the core member 1 is composed, are first assembled and insulated bythe flexible wrapping or sheath 2, then the coil 3 is wound thereon and is insulated by the outer 'fiexible wrapping or sheath 4. Finally, the

end members 7 and 8 of the casing are bolted together to rigidly clamp both the coil and the core member of the transformer between them.

If a sudden rush of current should pass through the conductor 15, a corresponding rush would circulate through the winding 3, but, inasmuchas the turns of this winding are uniformly distributed about the core member and are clamped in position by the casing 5, the winding will not be displaced.-

This is evident from a consideration of the forces existing in the transformer when the rush of current occurs. It is well understood that a' repulsion always obtains between the primary conductor and the secondary coil and this is greatly aggravated when the current traversing one of the windings is suddenly increased. As thefturns of the secondary coil are uniformly distributed about the primary conductor in my transformer, the forces acting on the latter are neutralized. The casing effectively holds the secondary coil and the core member and,

consequently, the transformer is specially adapted for very severe service.

It is evident that the structural details illustrated may be modified within the spirit and scope of my invention.

Iclaim as'my invention:

1. A-transformer comprising an annular core member, a winding therefor having its turns uniformly distributed about the core member, a pair of annular. members substantially inclosing. the winding, means for forcing said members toward jeach other in order to press said winding againstopposite faces of the core member,.and a tubular insulator extending through the opening in the core member.

2. A transformer comprising an annular core member, a'winding therefor having its turns uniformly distributednbout the core In testimony whereof, I have hereunto member, an outer casing substantially insubscribed my name this 26th day of July,

closing the winding and. comprising a pair 1911. of flanged end members and bolts for elamp- WALTER M. DANN.

5 ing their inner faces agninstthe windin Witnesses:

and an insulating sleeve or bushing exten W. A. CLARK, ing through the opening in the core member. B. B. HINES. 

